We provide direct access to that Discord Server to all our members.
Just click on the join button, login and you are good to go.
You can even establish a direct synchronization between Portal and Discord.
This way you can use your Discord Avatar here on the Portal and your user-rights on the Portal will also be established on the Discord server.
Just go to your "Account Management" on your "Control Panel" and activate the Discord synchronization at the very bottom of the page.
